As a piezoelectric actuator, for example, there is known a construction obtained by enclosing, in a metal-made container, a piezoelectric element comprising: a columnar staked body including a plurality of piezoelectric layers and internal electrode lavers laminated; and a pair of external electrodes attached to side surfaces of the stacked body so as to extend in a stacking direction thereof, respectively, each of the external electrodes being electrically connected to every second one of the internal electrode layers in an alternate manner (refer to Patent Literature 1, for example).